diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-02-11 11:32:38 +1100 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-02-11 16:07:37 +1100 |
| commit | cd15b048445d0a54f7147c35a86c5a16ef231554 (patch) | |
| tree | 80c7e63624143adc5d453106ec13f445438c6135 /arch/powerpc/platforms/powernv/pci.c | |
| parent | ea961a828fe7250e954f086d74d9323c3d44c3e4 (diff) | |
powerpc/powernv: Add iommu DMA bypass support for IODA2
This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.
Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/platforms/powernv/pci.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/pci.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index b555ebc57ef..95633d79ef5 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -634,6 +634,16 @@ static void pnv_pci_dma_dev_setup(struct pci_dev *pdev) pnv_pci_dma_fallback_setup(hose, pdev); } +int pnv_pci_dma_set_mask(struct pci_dev *pdev, u64 dma_mask) +{ + struct pci_controller *hose = pci_bus_to_host(pdev->bus); + struct pnv_phb *phb = hose->private_data; + + if (phb && phb->dma_set_mask) + return phb->dma_set_mask(phb, pdev, dma_mask); + return __dma_set_mask(&pdev->dev, dma_mask); +} + void pnv_pci_shutdown(void) { struct pci_controller *hose; |